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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 3/8"-16 Int Thrd Sz, 9/16"-12 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 3/8"-16 Int Thrd Sz, 9/16"-12 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, inch-system mil. spec. insert with 4 keys, 3/8"-16 internal thread and 9/16"-12 external thread, plain finish, 10 per pack. It meets MS51831-204, is made from…

SKU 3G-OTH-531644

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, 3/8"-16 Int Thrd Sz, 9/16"-12 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-076304
Type
Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Ext Thrd Sz
9/16"-12
Finish Type
Plain
Int Thrd Sz
3/8"-16
Thread Type
Coarse
Industry Standards
MS51831-204
Compatible Tap Size
9/16"-12
External Thread Fit
2A
Internal Thread Fit
3B
Material Grade/Class
18-8
System of Measurement
Inch
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APPROVED VENDOR Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The APPROVED VENDOR Key Locking Insert is a heavy-wall, inch-system mil. spec. insert with 4 keys, 3/8"-16 internal thread and 9/16"-12 external thread, plain finish, 10 per pack. It meets MS51831-204, is made from 18-8 material with 2A external and 3B internal thread fits, and is compatible with a 9/16"-12 tap.

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert repairs or reinforces tapped holes in softer materials. The external keys lock the insert in place, preventing rotation under load. This heavy-wall, 18-8 stainless steel insert meets MS51831-204 and is used in aerospace, defense, and industrial maintenance applications.

What are the specifications of the APPROVED VENDOR key locking insert?

This heavy-wall insert has 4 keys, a 3/8"-16 internal thread, and a 9/16"-12 external thread. It is made from 18-8 stainless steel with 2A external and 3B internal thread fits, plain finish, and meets MS51831-204. It comes in a 10-pack and is compatible with a 9/16"-12 tap.

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies APPROVED VENDOR key locking inserts worldwide. As a global industrial sourcing partner, we handle logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on the 10-pack of heavy-wall inserts meeting MS51831-204.

How to install a key locking insert?

Installation requires tapping the hole to the specified external thread size (9/16"-12), then driving the insert into the tapped hole using a compatible installation tool. The keys engage the parent material to lock the insert. Follow standard mil-spec installation practices for MS51831-204 inserts.

Used in

Common applications for APPROVED VENDOR
Laboratory sampling — APPROVED VENDOR clear wide mouth glass bottles for collecting and storing liquid samples in non-sterile environments.
Steam heating maintenance — APPROVED VENDOR forged brass radiator valves for regulating steam flow in commercial building heating systems.
High-pressure cleaning — APPROVED VENDOR turbo spray nozzles for pressure washers used in industrial equipment cleaning up to 6,000 psi.
Cleanroom operations — APPROVED VENDOR vinyl task chairs for seating in ISO 5 classified manufacturing or assembly areas.
General sealing — APPROVED VENDOR natural rubber stoppers for closing laboratory flasks or test tubes in educational or research settings.
Tamper-evident security — APPROVED VENDOR brass lead and wire seals for securing utility meters, cargo containers, or access panels.

APPROVED VENDOR Products

3G Electric supplies APPROVED VENDOR mil. spec. key-locking inserts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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